The present invention relates to an adhesive tape, and more particularly to a safety adhesive tape, which can easily be pulled apart with the hands or cut with a cutter.
Adhesive tapes are intensively used in packing thinks. A regular adhesive tape is generally comprised of a base layer, an adhesive layer, and an anti-sticking layer. The base layer for a conventional adhesive tape has sufficient tensile strength and elongation. Because the base layer of a conventional adhesive tape is resilient, it is difficult to pull apart a conventional adhesive tape with the hands. Further, the present inventor invented an adhesive tape on which the user can print a printing, draw a pattern, or write words.
The present invention has been accomplished under the circumstances in view. It is one object of the present invention to provide an adhesive tape, which can easily pulled apart with the hands, or cut with a cutter. It is another object of the present invention to provide an adhesive tape, which allows the user to write on it. According to one embodiment of the present invention, the easy-to-tear safety adhesive tape comprises a base layer, a hard resin layer, an adhesive layer, and an anti-sticking layer. The base layer is a long, narrow, flat piece of plastic material, having a top side and a bottom side. The base layer is formed of polyester film, bi-axially extended polypropylene film, or polyvinyl chloride film, having a thickness within about 0.008 mm to 0.08 mm, or preferably within about 0.01 mm to 0.05 mm. The hard resin layer is selected from acrylic resin, ethylene polybenzene resin, or polyamino-methylurethane resin group, and coated on the top side of the base layer, having a thickness within about 0.002 mm to 0.04 mm, or preferably within about 0.004 mm to 0.02 mm. The adhesive layer is selected from hydrophilic acrylic glue, oil acrylic glue, or thermo-bonding glue, and coated on the bottom side of the base layer, having a thickness within about 0.001 to 0.03 mm, or preferably within about 0.05 mm to 0.01 mm. The anti-sticking layer is selected from silicone resin or a wax of low molecular weight, and coated on one side of the hard resin layer opposite to the base layer. The amount of coating of the anti-sticking layer is within about 0.0002 gm/m2 to 20.0 gm/m2, or preferably within about 0.002 gm/m2 to 2.00 gm/m2. In order for writing upon, a writing layer is sandwiched in between the hard resin layer and the anti-sticking layer. The writing layer is formed of a resin mixture. The resin mixture is composed of a resin and an additive. The resin for the resin mixture is composed of at least one of acrylic resin, polyamino-methylurethane resin group, and epoxy resin. The additive is composed of at least one of calcium carbonate, silica, and titanium white powder. The resin mixture is prepared at the ratio by weight within about 1000:1 to 10:1, or preferably within about 100:1 to 20:1. This thickness of the writing layer is within about 0.0001 mm to 0.05 mm, or preferably within about 0.001 mm to 0.01 mm. The safety adhesive tape can be rolled up in a roll on a reel or the like without the use of a stripping paper. When rolled up, the adhesive layer is pressed on the anti-sticking layer. The anti-sticking property of the anti-sticking layer enables the anti-sticking layer to be used as a stripping paper. The anti-sticking layer protects the adhesive layer, and can easily be separated from the adhesive layer. When in use, the user can directly pull apart the adhesive tape with the hands subject to the desired length. Because no stripping paper is used, no litter is produced. Because the adhesive tape has a hard resin layer (which reduces the elongation and breaking strength of the adhesive tape), the adhesive tape can easily be pulled apart with the hands.